A Semiconductor DNA Sequencer

Speed sequence: Ion Torrent’s semiconductor chip (shown here) can sequence samples of DNA in just a few hours.

Last December, Ion Torrent, something of an upstart in the sequencing industry, launched its new semiconductor-based sequencing machine. At $50,000, it was a comparatively inexpensive device designed to move DNA sequencing from large, specialized centers to the standard lab bench. Now the company says its machine is en route to becoming the most popular one in a competitive market.

Life Technologies, which bought Ion Torrent for $375 million in cash and stock last August, is feeling good about its bet. The technology has already proved its worth as a valuable public health tool. In June, two different groups used the Ion Torrent machine to rapidly sequence the genome of a new strain of E. coli that killed more than 20 people in Europe. The effort helped identify the microbe’s drug-resistance genes. And researchers across the globe are using it to sequence genes involved in cancer and other diseases, with the aim of creating rapid tests to determine the best medicine for a patient.

Ion Torrent is competing with a number of sequencing technologies, all racing to become the fastest and cheapest: a landmark goal in the field is to sequence an entire human genome for $1,000, which would put it on par with many other routine medical tests. But Jonathan Rothberg, Ion Torrent’s founder, says his technology, which is based on semiconductors, is getting better faster than anyone else’s.

Most advanced sequencing technologies rely on fluorescently tagged molecules and a microscope to sequence DNA. At the heart of Ion Torrent’s machine are sequencing chips that detect DNA sequences electronically. This approach removes the need for expensive lasers and cameras. The chips are made in the same semiconductor fabs as computer microprocessors. And just as with computer chips, production costs per chip drop as larger numbers are produced. As sales of the Ion Torrent machine have risen, the cost of the sequencing chips has dropped from $250 to $99.

Researchers have also improved the chip’s sequencing capacity by tenfold; each chip can generate 100 million base pairs, up from 10 million base pairs when the technology first launched. Rothberg says a third-generation chip capable of sequencing a billion bases will be available next year.

As a tip of the hat to the power of superconductors, Ion Torrent has now sequenced the full genome of Intel cofounder Gordon E. Moore, now 82. Moore is best known as the creator of Moore’s law, which posits that the processing power of new chips would double approximately every two years. Ion Torrent’s chip has improved tenfold over six months, a rapid advance that Rothberg attributes to “accumulated Moore’s law,” or the decades of research and billions of dollars that have gone into making faster microprocessors.